Formed parts are generally created via molds, dies and/or by thermal shaping, wherein the use of molds remains the most widely utilized. There are many methods of forming a part via a mold, such as, for exemplary purposes only, stretch-blow molding, extrusion blow molding, vacuum molding, rotary molding and injection molding. Injection molding is one of the most popular methods and is a method wherein the utilization of auxiliary equipment, such as machine vision methodology, can increase efficiency via improved quality of task performance and increased part production.
Machine vision systems are exemplary auxiliary components that are relied upon throughout a vast array of industries for computerized inspection of parts and assistance in, direction of, operational control of automated and semi-automated systems for the production and/or manipulation thereof. In each instance, a variety of sensory data is acquired from a target site and is analyzed by a computer according to a comparative or otherwise objective specification. The analysis results are reported to a controller, via an I/O board, whereby machine decisions are influenced and/or actions are directed as a result thereof.
Robots are often utilized, wherein machine vision systems may be coordinated therewith to influence the operation thereof via communications regarding a part. As such, signals to and from the part-forming machine controller in response to the image analysis are critical to ensure proper and timely automatic cycling. These signals must be swiftly and accurately communicated to the robot controller, and vice versa.
Robots can be configured and utilized for a variety of duties related to tending molding machines, taking the parts and sprue from the mold, loading inserts such as studs, bushings or fittings and depositing parts at an appropriate station, thereby keeping operators away from dangerously hot molds and ensuring repeatability of operations. For example, a robot can be utilized to demold complex shapes and handle upstream or downstream operations, grasp a workpiece, and/or perform various operations thereon, such as, plastic welding, component assembly, and drilling. Where variations are inherently introduced by the system, such as from part shrinkage during cooling after plastic blow-molding, precise information is necessary for robots to accurately locate and identify a target workpiece and to prevent robot collisions. In one system, a plurality of cameras view images of each plastic part from a variety of angles, comparing same with ideal part dimensions in order to report offsets for robot path adjustment. In this manner, automation can be adapted in response to vision guidance. Further, more sophisticated robots can perform part inspection, degating, printing, labeling and packaging, often serving more than one machine.
Typical systems require the use of separate communication interfaces to process signals between a machine, a robot, and auxiliary devices, such as vision system components. This methodology disadvantageously duplicates I/O interfaces. Further, while each robotic implementation and sensory improvement can and does increase quality and productivity for part-forming processes, as well as other machine applications, resultant complexities in communications and attendant electrical risks between components introduce practical limitations. Therefore, the maintenance of electrical isolation for each major component is desirable.
Therefore, it is readily apparent that there is a need for an auxiliary communication system and method, wherein system components can be electrically isolated, wherein a machine controller and a robot can communicate according to standard protocols, and wherein auxiliary equipment can be incorporated into the communication system, thereby alleviating the need for and the limitations of auxiliary I/O boards and avoiding the above-discussed disadvantages.